atw - International Journal for Nuclear Power | 2.2024

Environment and Safety
49
obtaining a license, the CNSC evaluates the limits of
radiation exposure during potential accidents based on
the design and ensures that the prescribed distance of
the exclusion zone is suitable to fulfill all safety
standards. The CNSC collaborates closely with the province
(s) in sharing details about the safety case and
licensing process of the nuclear facility. This information
aids the province in making decisions regarding
the establishment of the EPZ [41] .
4.2 U.S.A
According to NRC regulations, the agency must determine
if licensee, state, and municipal emergency plans
are sufficient and feasible to implement before granting
a license for a nuclear power reactor. The NRC/EPA
Task Force Report on Emergency Planning (also known
as NUREG-0396) established the sizes of these EPZs,
which are partially based on the PAG (Protective Action
Guide) values for the plume exposure and ingestion
route EPZs [42].
4.3 United Kingdom
To guarantee that all potential risks – LOCA, non-LOCA,
internal, and external – are recognized and that
adequate safety precautions are taken to safeguard
both human health and the environment, the safety
case for the SMR is being created in a methodical
manner based on approved techniques. To date, and to
our knowledge, no effort has been made to define the
UK SMR‘s EPZ. The Office of Nuclear Regulation (ONR)
will make the final decision regarding EPZs. This
decision will consider a variety of factors, including
site-specific considerations, the technical evaluation of
the plant (e.g., source term) and its operating procedures,
and other factors that the ONR Emergency
Preparedness and Response Team has taken into
consideration [43] .
4.4 South Korea
The 365 MWt SMART reactor is a compact reactor that
will be deployed in Saudi Arabia or South Korea. The
SMART reactor requires the establishment of a smaller
emergency planning zone (EPZ) due to its smaller size
compared to conventional nuclear reactors. Moreover,
the USA and IAEA have differing requirements for EPZ.
Following the Fukushima Accident, Korea‘s EPZ mandate
was essentially shifted from the USA’s to the more
restrictive IAEA’s [44] .
4.5 China
Early EPZ development for HTR was tested on the U.S.
Department of Energy‘s Modular High-Temperature
Gas-Cooled Reactor (MHTGR). The NRC examined the
MHTGR‘s safety and recommended that advanced
reactor design elements serve as the foundation for
emergency preparations. The current general framework
of LWRs is also followed in the calculation and
analysis of EPZ for HTR-PM. The technical framework
introduced by NUREG-0396 is adopted, and the
principles and methodology for EPZ development of
LWRs are published in China‘s national standard [45] .
The Chinese EPZ contains the Plume Emergency Planning
Zone (PEPZ) and Ingestion Emergency Planning
Zone (IEPZ). The set and size of EPZ for NPP normally
refer to the national standard emergency plan and
preparedness criterion part I: Based on the national
standards, the PEPZ includes inner zone and outer
zone. The size of PEPZ generally is about 7~10 km
and the inner zone is about 3~5 km, considering heat
power of the reactor and radiological consequences of
postulated accident sequences as well as political
factors. IEPZ can be considered with results of accident
radioactive consequence assessment in the stage of
emergency plan and preparation [46] .
4.6 Japan
After the Fukushima Daiichi accident, March 11, 2011,
the overlapping regulatory and nuclear energy
advocacy practice of nuclear power was re-organized
due in part to national lessons learned, during “3.11”
but also, many external studies and higher-level
feedback provided. In particular, wider expectations
(and/or regulatory requirement) to use probabilistic
risk assessment (PRA) and to better address risk and
crisis management and communication, were key
findings.
The former regulatory structure was reorganized and
renamed the Nuclear Regulation Authority (of Japan)
and is today, an administrative body of the Cabinet
of Japan, that was established to ensure nuclear safety
in Japan, as part of the Ministry of the Environment. It
was established on September 19, 2012, with its first
head [47] .
With respect to emergency response which may or may
not be linked to an unplanned release of radioactivity,
from a protected site (such as a nuclear generation
station), aspects worth noting are:
⁃ The permissible level of exposure to low level radiation
by the general public is ~20 millisievert/hour
OR
⁃ Stabilized iodine tablets are no longer restricted to
age 40 but some 4.8M people live within 30km of a
nuclear reactor, production of these pills would
require time and require a supply chain of more
than one pharmaceutical firm. This is ongoing.
⁃ An Urgent Protective action planning Zone, (UPZ) is
approximately 30km radius. There are additional
regulations beyond the 30km. Within the first 5 km
is the Precautionary Action Zone (PAZ), the UPZ is
defined from 5~30km and outside the UPZ, 30km
and beyond.
⁃ At least 3 levels of Emergency Action Levels (EALs)
and at least 4 types of Operational Intervention
Levels (OIL) define the UPZ, as short as 5km. Additional
details are described by Hirano [48] .
Vol. 69 (2024)